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Bf25 lower unit drain plug stripped

Man! That's a tough one! That housing is pretty thin in that area

I don't have any great answers for you.

One thing that crossed my mind is the spark plug hole repair kits for aluminum engine heads. But there's way more material to work with on those.

I have used epoxy thread repair kits (Loc-Tite makes a good one) for thin aluminum governor housing cover screws but that stuff is touchy to work with. I also don't know if it would make a strong enough new thread for getting a good oring seal down there. If it fails, your transmission will have no oil and be full of water in no time.

You could have a small plug piece tig welded into the hole then drill and tap it for a brass pipe plug. It would look wierd but would definitly work.

Meanwhile I'll be watching to see what others come up with and maybe learn something good.

Good luck.
 
On inspection there is lots of depth and thread for an extended length plug .... now just need to find one.
Edit... on closer inspection... only on one side... but I see there may be a 9mm plug available to go to larger thread
 
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Companies like Gates, Parker and Aeroquip make countersunk, oring seal plug caps for hydraulic reservoirs for things like floor jacks and porta powers. You might want to take your plug to a hydraulic repair or hose shop to see if they can come up with something that will work.

On a different subject, are you getting the same spam messages that I'm seeing in your inbox?

It's like this site is under attack. I keep reporting it but never hear back from the moderator. It's been happening for about a week now.

Either way, good luck with your drain plug.
 
jgmo said:
It's like this site is under attack. I keep reporting it but never hear back from the moderator. It's been happening for about a week now.
Click to expand...
Appears to be. I also have been reporting the non marine spam. I tap on the “members” name and hit ignore then refresh the website. Makes navigating the posts easier without the garbage.
 
This may be the answer.
 

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Pricey little devils, aren't they? But it does look like it might fit the bill.
Let us know if that's what you go with.
Good luck.
 
Oh!
Now I see it's "3 pieces" so "only" $11 per copy:)

I didn't see the thread pitch mentioned or, did I miss that?
 
Any Johson / evinrude / mercury or " no name " boat shop would have a 3/8-16 drainplug laying around for $2.00 I think.
 
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